My 05 caravan was fine. Everything worked. Turned it off and when tried to start it there was nothing. Not one light on the dash. No headlights, taillights, buzzers, beepers, NOTHING. I searched on line found some posts about the fuses and relays. Unplugged and switched some of them around in the fusebox.
Suddenly everything is fine. Drove it home. Next day noticed there were no tail lights. Everything else including brake lights, signals, and stop lights working fine. Just no rear running lights with the headlights on. Set out to trouble shoot that and NOW I'm back to NOTHING AT ALL! NO POWER TO ANYTHING. I have tested all of the relays in the fusebox with a meter (continuity between 87a and 30). They are fine. Fuses are fine. Previously (when everything else was working) while checking I found that there was no power to the taillight fuses in the box. Electricity has always seemed like VOODOO to me! HELP! PLEASE

 

You could try a tap/wiggle test on the IPM and bottom connections with the key on and see if something comes alive. Take a close look at the crimped on battery connections where the cable is crimped on the connector. They sometimes loosen up and cause intermittent headaches.You could unbolt the IPM - fuse box, rotate it up and access the connectors on the bottom. As I recall you may have to remove the battery first. Disconnect and inspect for signs of corrosion or any damage. While you're there make sure the battery power feed connection at the IPM from the battery is clean and tight. The IPM is a known trouble spot for just about anything electrical on these vans.

You could test for power at the starter relay to verify the ignition switch is allowing power through. Remove the relay and with a meter, check for power at contact 86 on the IPM with the ign switch at start. If there's no power check for power at the ignition fuse (10 amp fuse 23). Can do the same at the fuel pump relay. If there's no power there you're back to an IPM problem. Could be a bad circuit board in it.

BTW-Testing 30 to 87A is only telling you have continuity on the output contacts when the relay is de-energized. Pretty useless. A better test is to check the resistance of the coil in the relay at contacts 86 to 85 on the relay. Even better - bench test it using a power supply. Then there's what most of us do - swap them into another system and see if that system fails.

Need wire diagrams? Send me a private message and include an email address to send them to. How? Click Cougar41 at left.

 

I'm with you on the IPM.

 

Hey thanks guys for the responses cuz I had no clue what to do next. I already pulled up the IPM (fusebox?) and pulled every plug on the bottom and cleaned them with contact cleaner and a little wire brush. I will try the different tests on the relays. Can't plug into a different system - NONE of them works. I will check for ignition power as instructed. At least now I have SOMETHING to try. Seems weird that it could work perfectly and then 10 minutes later -------nothing. Almost have to be a bad connection somewhere wouldn't it?
I remember a few years ago I was having weird electrical problems with this van and I got a recall on the headlight switch. Replacing that solved the intermittent glitches that time. It's at 150 thousand miles, could the ignition switch be worn out?

 

Ok, I cleaned all the connections(and applied dielectric grease) and yay! I have power to everything except the tail lights once again. Now back to the original repair. What do I do about the tail lights? I have power to the tail light fuses in the IPM but no tail lights. Don't see how the brake lights, signal lights, and back up lights can work and the tail lights not work. I checked the bulbs and sockets. What now??????????????

 

Wiring diagram would be next. Track down the open ckt. It could still be related to the IPM or the FCM which is attached to it.

 

Check the license plate bulb and wires. Mine was broke and it would cause the fuse to blow for the taillights over and over and over.